We bore witness to enduring history last night, the kind of event that boxing aficionados will talk about for generations. And it's not too early to play boxing historian, either; it's often better to wait more than a day before foisting such sweeping declarations on a thing, because it is the nature of history for the long view to be the sharper-eyed one. But when Juan Manuel Marquez knocked out Manny Pacquiao Saturday night, any number of automatic, identifiable triggers were pulled, beyond the intuitive feeling from every boxing fan who saw it that they had just seen something they would never forget, something that was imprinted on their brains via instant flash burn.

That knockout was one of the most shocking one-punch KOs of a high level fighter ever. It's already been compared, rightly, to the likes of Thomas Hearns-Roberto Duran in 1984. Its nearest competitor is Sergio Martinez-Paul Williams II two years ago, and as highly-regarded as Williams was, he had no status as an all-time great, the way Pacquiao has. Pacquiao's knockout of Ricky Hatton in 2008 doesn't come that close because Pacquiao was the favorite to win.

It was the best episode yet of the Pacquiao-Marquez rivalry, one that spans eight years and five divisions, beginning at featherweight and working its way up to welterweight. Since the turn of the millenium, the Pacquiao-Marquez series of fights counts among its peers only Arturo Gatti-Micky Ward, Israel Vazquez-Rafael Marquez and Marco Antonio Barrera-Erik Morales. Some of those others featured better individual fights. None of them featured fighters as good as Pacquiao or Marquez.

It will almost certainly end 2012 as the Knockout of the Year; Round 5 will be a strong contender for Round of the Year; the fight itself is a contender for Fight of the Year; and the win might make Marquez the Fighter of the Year. Marquez climbs the list of best Mexican fighters ever by doing what Barrera and Morales could not, which is to destroy Pacquiao, once known as "The Mexicutioner." The record-keepers who etch these kinds of things into books will, in a more permanent way, seal the enduring history of Saturday night.

And, look, this kind of mathematical method of parsing Marquez-Pacquiao 4 in a way turns it into a more clinical thing than it was. This was Mitt Romney's expression when Pacquiao dropped face-first in front of him as he sat ringside. This was Pacquiao's wife Jinkee flying into hysterics. This was the slow-motion replay of Marquez, blood trickling from his broken nose, catching a lunging Pacquiao with a punch of exquisitely destructive beauty. This was the scream of surprise from everyone who watched it happen. This was an idol of the sport laying helpless on the mat, the way he had left so many opponents before. This was boxing fans unable to type messages to their friends with trembling hands, unable to sleep because of the adrenaline coursing through their bodies. Maybe Sportscenter didn't see this as worthy of one of its 10 "Top Plays." But boxing fans know — in their bones — what they saw.

The long view might add additional shading for the better. There is one way where the passage of time might turn this event into a pivotal, ugly moment for the sport, in fact. We consider these things now.

Juan Manuel Marquez

This fight forever changes the legacy of Marquez. He already had a claim to best Mexican fighter of his generation over Morales and Barrera, but this cements it. For all he accomplished — and it's true that it was one of the more underrated set of accomplishments in the sport prior to Saturday — had Marquez never beaten Pacquiao, he would have gone down as the man who almost beat Pacquiao, or who beat Pacquiao three times without getting credit for it. Cold, hard win-loss records, though, have a way of persisting better than memories and perceptions. You could dispute Marquez's draw with Pacquiao or his two losses. It is harder to dispute something as vivid as the letter "W."

Nor can you dispute one of the ways Marquez did this: Superior ring intelligence. There is only one night in Marquez's career where he was definitively outsmarted, and that was against Floyd Mayweather. You can trace it back to the very first round of this rivalry, where Marquez was blitzed and dropped three times before he learned how to handle a physical marvel who had every advantage of speed and power and everything else that is in a boxer's body short of his brain. It is timing, it is spacing, it is the ability to make small adjustments where Pacquiao struggled to do the same. Each time they met, Pacquiao came into the fight with a different game plan, one that, on paper, had a chance of working. Each time they met, Marquez struggled with it, then overcame it. Pacquiao's physical advantages always manifested themselves; even the smartest fighters would have difficulty contending with those gifts. But Marquez figured Pacquiao out better every time they fought. Watch the first knockdown of the bout, but, first, rewind a little; notice that while Pacquiao was dialing in his straight left, Marquez was hammering Pacquiao with hard body shots. Then, on the knockdown, note how he faked a body punch with his left just enough to make Pacquiao alter his defenses, and then watch that looping overhand right sneak in and deck Pacquiao.

You can dispute one of the other ways he might have done it. Marquez, for the third meeting with Pacquiao, passed the threshold of reasonable suspicion of performance enhancing drug usage. When you have Angel Heredia, now going by the name Hernandez, in your corner, you are going to arouse reasonable suspicion. Hernandez is a former BALCO chemist who keepssaying and doing peculiar, suspicion-arousing things, like changing his name; like saying he has nine other boxing clients and not naming them; by saying he's willing to have his fighters tested and then not having them tested, or saying that they have been already, but not saying by whom; by bragging not so long ago how easily he could beat drug tests; etc. For the fourth meeting, Marquez aroused even more reasonable suspicion, for that absurd physique of his for a 39-year-old fighter and for hurting Pacquiao worse than he had ever been hurt in any of their meetings. There is no conclusive evidence of misdeeds here, but there are reasons to deeply worry that we just haven't seen the conclusive evidence that exists out there somewhere. Whether we ever will, given the state of testing and Heredia's expertise, is a great unknown.

There are, likewise, reasonable counters to the suspicion about Marquez. A lot of athletes have retained their vitality in their older years without ever having been found to abuse PEDs, and perhaps you can chalk that up to improved training methods, nutritionists, and better science rather than dark alchemy. Marquez has traversed no more weight classes than Pacquiao, who retained much of his power and even enhanced it while moving up in weight over the years. Marquez surely didn't look in his welterweight debut against Mayweather like he had done anything smart whatsoever in adding the weight, chubby fellow that he was, and perhaps he just applied proper methods to the task this time and the last one. And that knockout power? You simply cannot land a better punch on a human being than that one. Pacquiao literally jumped into Marquez's shot at the precise moment when that right was at the most damaging split second of its arc. As well, maybe that knockout said something about where Pacquiao was as a fighter at this point in his life, a point of discussion a little later.

(By the way, Pacquiao himself, once accused by the Mayweather clan of using PEDS without any evidence, has subsequently accumulated a bit more circumstantial evidence of potential use, like a propensity for leg cramps or a few troubling indicators involving his own strength coach Alex Ariza. And Heredia isn't the only former BALCO figure skulking about in boxing right now with clients. Victor Conte doesn't, to my mind, deserve a pass because he's affiliated with the Voluntary Anti-Doping Agency, or because he did jail time and Heredia didn't. Both of these men cast themselves as reformers, yet despite Conte's association with VADA, VADA busted one of his clients, Andre Berto, earlier this year, with a banned substance in his body; and there's something untoward about Conte advising VADA — in effect helping write the tests — and then advising people who are being tested. All three of these men could be innocent, or, in the case of Heredia and Conte, could have turned over a new leaf. But their presence in the sport that just happens to have about the most extremely lax drug testing requirements of all is discomfiting.)

For now, it is fair to question whether some kind of chemical sorcery was at play here. If we find out that it was, this knockout will mutate from one of the sport's defining amazing moments to one of its defining disgusting ones, and hopefully a moment that would advance the sport's attitude toward PEDS from one step forward/two steps back to one of real change. More likely, we never find out for sure and a cloud of doubt hovers over Saturday night. One way or the other, Marquez got a career-defining victory this weekend. Time will tell how glorious, or ignominious, a victory it was. Until then, it's hard not to be at least a little happy for Marquez shedding the label of this era's longest-unwed bridesmaid.

Manny Pacquiao

Ironically, Pacquiao had been well on his way to winning the fight definitively himself before he got starched. He had been fighting well, and doing more damage to Marquez than Marquez was doing to him over nearly six rounds. Marquez's stand in the 5th was impressive in part because Pacquiao was putting it on him in such a frightful way. Pacquiao's eyes had a hard focus about them, a kind of visible determination that the happy-go-lucky warrior rarely displays. He looked like "elite Pacquiao," not "so-so Pacquiao."

But you have to wonder if all those years of distractions, the marriage drama and the political career and the acting and singing, caught up with Pacquiao the boxer. He showed up for camp later than his trainer Freddie Roach wanted, yet again. He hosted a fundraiser for Hurricane Sandy close to the fight. Pacquiao has shown great ability to fight through distractions, but they've also hurt him in some fights. He's talked of retiring for a long time, and at one point he was wrestling with whether boxing contradicted his Christian faith. Boxing training takes a kind of devotion that exceeds so many other commitments, and training for boxing at the elite level requires an almost demonic and solitary obsession.

Or perhaps the years have simply caught up with Pacquiao. He's turning 34 in a little more than a week. He began fighting at age 16. A great many of his fights were of the grueling sort. Few boxers can take the kind of punishment Pacquiao has over his career and still be elite. He had shown signs of decline well before, with some tracing the beginning of his decline to his May, 2010. His chin has always held up, but the cliche of a fighter "aging overnight" is a cliche for a reason: It happens. There's a moment when all the years and fights chip away at the essential qualities that made a previously invincible fighter disappear, rendering him rather -vincible. Pacquiao, always a class act, has made no excuses for his loss. Given some of his pre-fight comments about Heredia and Marquez's physique, I wouldn't be surprised to see Roach break that silence.

There is no shame in Pacquiao, after years of decline, getting stopped by his greatest and most difficult rival, even if that man was 39 years old. Marquez remained one of the five best active fighters, despite that age. What's more, this is boxing: People get knocked out sometimes. It is more impressive for a boxer to sustain the kind of streak Pacquiao has in fighting the elite fighters he has WITHOUT getting knocked out than it is for Mayweather to have spent so many years of his peak ducking top competition and doing the same.

Which brings us to that old debate. Some hardcore Mayweather fans were just salivating while waiting for a moment like this, when they could say, "See? We told you he was never that good." But nothing about this night erases anything that Pacquiao accomplished before. He was the Fighter of the Decade; he is the only man with four legitimate lineal championships ever; he is arguably one of the 20 best fighters that ever lived. You can pick apart his individual wins the same way you can pick apart any fighters' wins. But when a boxer keeps beating elite and/or all-time great fighters over and over and over and over again, it becomes hard to negate the entire body of work. Plain and simple, you don't beat the guys Pacquiao has beaten if you were not that good. Nobody else in this era has beaten as impressive a roster of fighters, including Mayweather. Mayweather fought the best early in his career, and with the notable exception of Pacquiao, has tangibly improved his competition in the last few years, but he had a long empty period where he wasted his talent. Now, with Pacquiao-Mayweather spoiled — it was certainly diminished by the passage of years, as Pacquiao began to slide — the one person Mayweather could've beaten to end the argument would do no such thing for him. For as much as both bore the brunt of the blame for not making the fight happen, Mayweather owns more of that blame.

What's next, then, for Pacquiao and his sport? I have no interest in Pacquiao-Marquez 5. I have no interest in any rematch of a fight that ends like that one. Perhaps Pacquiao can recover from such a devastating knockout; that kind of thing has happened before. Perhaps he could even beat Marquez in a fifth meeting. If that happened, maybe Pacquiao could add to his legacy. But his legacy is secure no matter what he does next.

If he retires, we will have lost one of the two men (along with Mayweather) who have ruled boxing financially and atop the pound-for-pound rankings for so long. Inevitably, panic will set in for boxing fans. Mayweather isn't much longer for the sport himself, as his own physical assets have begun to fade. I, however, feel as good about the next generation of stars as I ever have since Mayweather and Pacquiao took the baton from Oscar De La Hoya and people began worrying immediately about what would happen when those two left, too. Andre Ward and Adrien Broner are both elite talents and nice draws, but we still don't know if they can ascend to the financial heights of Pacquiao or Marquez. Saul Alvarez and Julio Cesar Chavez, Jr. are outrageous draws and nice talents, although we still don't know if they have the talent to carry them to the top of the sport for any prolonged period of time. Between those men, someone will likely emerge to take over for Pacquiao and Mayweather.

If this is the end for Pacquiao, it could not have been a better ride. He's given us so many of those images of the kind I mentioned before, that are seared into the mind: that "Oh, shit, we're watching the birth of a star" display against Barrera; the scary knockout of Hatton; the wars with Morales; the toppling of the odds against De La Hoya; even the awkward performances of "Sometimes When We Touch." Saturday, he was part of another one of those memories. It's a devastating loss, for sure, and his fans no doubt are morose today. It wasn't the part he wanted, or that his fans wanted. But that's the way gunslingers like Pacquiao often go down: pistols blazing. They wouldn't be who they were, for good and ill, or who we love, otherwise.

(Amazing photo of the knockout moment by Julia Jacobson of the AP, via.)

About Tim Starks

Tim is the founder of The Queensberry Rules and co-founder of The Transnational Boxing Rankings Board (http://www.tbrb.org). He lives in Washington, D.C. He has written for the Guardian, Economist, New Republic, Chicago Tribune and more.

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